SanDisk (SNDK) was downgraded at Summit Research to hold from buy. Valuation call, based on a 12-month price target of $87, Summit Research said.

Tyson Foods (TSN) was downgraded at Credit Suisse to underperform from neutral. Twelve-month price target was lowered to $35. The company expensively settled bidding war with Pilgrim for acquisition of Hillshire, Credit Suisse said.

Twitter (TWTR) was upgraded at Wells Fargo to market perform from underperform. Company is showing an Impressive utilization of its mobile platform and the risk/reward appears more balanced, following the recent weakness, Wells Fargo said.

Union Pacific (UNP) was upgraded at RBC Capital to outperform from sector perform. Twelve-month price target is $115. Company has solid growth potential and low earnings volatility, RBC Capital said.

Wendy's (WEN) was downgraded at Argus to hold from buy. Twelve-month price target is $8.50. Franchising could continue to weigh on sales in the coming quarters, Argus said.

Follow TheStreet on Twitter and become a fan on Facebook.

>>Read More:
3 Mysterious Things Now Happening at Chipotle

Porsche Electric vs. Tesla

This article was written by a staff member of TheStreet.

If you liked this article you might like

Caterpillar Leads Dow to Records, S&P 500 Also at All-Time Highs

Cramer: Nvidia Is More Than Just a Pet Name

S&P, Dow Close at Record Highs, Brushing Off Geopolitical Concerns

Stocks Shake Off North Korea and London to Stay in Record Territory

Will the Plunge in Bitcoin Crush AMD and Nvidia?